Question
Asked Sep 19, 2019
8 views
Uranium decays by first order kinetics. Given that the half-life of uranium is
4.47 billion years, what is the rate constant for the reaction?
If I originally had 25 grams of uranium, how much would I have left after
13.7 billion years (the age of the universe)?
help_outline

Image Transcriptionclose

Uranium decays by first order kinetics. Given that the half-life of uranium is 4.47 billion years, what is the rate constant for the reaction? If I originally had 25 grams of uranium, how much would I have left after 13.7 billion years (the age of the universe)?

fullscreen
check_circle

Expert Answer

Step 1

Given,

Order of uranium decay = 1st order

Half-life of uranium (t1/2) = 4.47 billion years

Initial mass of uranium (M0) = 25 g

Time (t) = 13.7 billion years

Part 1: For a 1st order reaction, half-life is expressed as:

help_outline

Image Transcriptionclose

0.693 t/2 where, t1/2 half-life k rate constant 0.693 k 4.47 billion yrs k 0.155 (billion years)

fullscreen
Step 2

Part 2: For a 1st order reaction, the int...

help_outline

Image Transcriptionclose

In At n Ao k x t where, At amount of A at time t Ao initial amount of A (at time 0) k rate constant t time In At n (25) - 0.155 (billion years)1 x 13.7 billion years In At 1.095 At 2.99 3.0

fullscreen

Want to see the full answer?

See Solution

Check out a sample Q&A here.

Want to see this answer and more?

Solutions are written by subject experts who are available 24/7. Questions are typically answered within 1 hour.*

See Solution
*Response times may vary by subject and question.
Tagged in

Science

Chemistry

Chemical Kinetics

Related Chemistry Q&A

Find answers to questions asked by student like you
Show more Q&A
add
question_answer

Q: 2.- Identify each of the following as a homogeneous or heterogeneous mixture. Explain your choice a

A: Click to see the answer

question_answer

Q: A 1.00 L rigid cylinder contains one mole of neon gas at 25 °C. Calculate the pressure using (a) the...

A: Given,Volume (V) = 1.00 LNumber of moles (n) = 1 molTemperature (T) = 25 oC = 298 K

question_answer

Q: Express each of the following numbers in scientific notation 47,500, 5,030,000, 0.0000470

A: Click to see the answer

question_answer

Q: How many joules are required to heat 75 grams of water from -85 ˚C to 185˚C?

A: Energy that required to heat water is calculated using the given formula,

question_answer

Q: In this problem I’m supposed to add the Hydrogens (originally not shown), valence electrons, and pi ...

A: The formal charge on an atom can be calculated by the following formula:

question_answer

Q: An unknown compound contains only C, H, and O. Combustion of 7.70 g of this compound produced 18.8 g...

A: An unknown compound contains only C, H, and O. Combustion of 7.70 g of this compound produced 18.8 g...

question_answer

Q: A mixture of C2H2 and CH4 has a total mass of 251.8 g. When this mixture reacts completely with exce...

A: Given:Total mass of mixture of C2H2 and CH4 = 251.8 g.Total mass of CO2 and H2O = 1138.0 g.Molar mas...

question_answer

Q: On another planet, the isotopes of titanium have the given natural abundances. Isotope Abundance ...

A: The average atomic mass of three isotopes can be calculated using the following expression:

question_answer

Q: How do I go by setting up the calculations to answer this question? How many nitrogen atoms are in 1...

A: 2 mols of N atoms are present in one mol of copper(II) nitrate [Cu(NO3)2].